Nikon EN-EL19 Coolpix S3100 Replacement Battery 3.7V 700mAh

NiKon Coolpix S3100 / S4100 / S2500 — 3.7V Li-ion Replacement Battery (EN-EL19)

This is a 3.7V, 700mAh Li-ion cell built to the EN-EL19 spec. It fits the NiKon Coolpix S3100, S4100, S2500, S6400, and more than 20 additional Coolpix compact bodies that share the same battery slot and connector. Voltage and physical dimensions match the OEM cell exactly: 39.60 × 31.15 × 6.10mm.

• Coolpix S-series compatibility: These Coolpix compacts share a common battery bay format and a 3.7V power rail. The EN-EL19 footprint is the same across the S2500, S3100, S4100, and S6400 lines — same connector orientation, same latch position, same BMS communication protocol.
• Bench tested on actual hardware: We cycled this cell through the S3100 body using the OEM charger. The BMS handshake completed on the first full charge cycle, and the battery-remaining indicator tracked consistently across discharge. No false-low warnings appeared after the initial calibration cycle.
• First-use charge cycle in the camera body: Insert the cell and charge it fully inside the camera via USB or OEM charger before shooting. Some Coolpix BMS firmware maps the voltage-threshold curve to the new cell only after one complete in-body charge cycle — skipping this step can cause the indicator to read low even when the cell holds charge.

Flash recycling slowdown on a new EN-EL19 cell near end of charge

The Coolpix S3100 flash capacitor draws a sharp recharge current after each burst. As the cell voltage drops toward the 3.0V cutoff, the camera cannot supply that current fast enough, and the flash recycle gap widens noticeably. This is not a fault — it is the BMS protecting the cell from over-discharge under high-current demand. If flash recycle time has slowed, check the battery indicator. If the cell reads below 20%, charge it before continuing flash-heavy shooting.

Battery percentage jumping erratically on the Coolpix display

The Coolpix S3100 maps its battery indicator to a fixed voltage-threshold table calibrated for the OEM cell's discharge curve. A new replacement cell may discharge along a slightly different curve, causing the indicator to skip segments — jumping from three bars to one bar without stopping at two. This is a display mapping issue, not a cell fault. Run two full charge and discharge cycles through the camera body, and the BMS recalibrates its threshold readings to the new cell's actual curve. After those cycles, the indicator steps down in normal increments.